Erik Wolpaw jokes, "We thought we should have a warehouse full of Hoopy t-shirts and mugs and posters…we would watch that hoop roll by over and over again. That was the part of the game we were most proud of, and nobody cared."

In Portal 2 it became a canon joke, by reappearing in some chambers (See "Portal 2" Below.).

Appearances

Portal

Portal 2

Hoopy is known to appear in a few places within Portal 2. Its earliest known appearance is in GLaDOS' ruined chamber, where it lays slightly to the left of what could be described as GLaDOS' head; its second known appearance is underneath a floor panel in Test Chamber 02. It then makes its third known appearance behind a desk in Rattmann's den in Test Chamber 06; this is the same den as referred to by the Final Transmission achievement.
Hoopy's fourth appearance is in one of the randomly-chosen exit corridors in chambers created with the Perpetual Testing Initiative. It is seen by noclipping into the ceilings of the exit corridor, although it doesn't appear in every one.